Degradation in calls to Cisco Unity

[dlopez2006_]

Hi, if someone has a issue like me,i hope someone can help.

 I have a CUC´n Rls. 9.1, when i call to any Extension and the call goes to VM, but in the call hear it noise or degradation , i check everyone of the components and it´s ok, the Router, Switch ports, CUCM, and CUC´s but i still has the same issue

Thanks

[dlopez2006_]

Any One Have any idea